Compact construction machines, for example compact track loaders, are commonly used in applications where working space is limited. These machines include a frame that may support an engine and work implement, and left and right undercarriages that transfer power from the engine to a ground surface. Some compact construction machines utilize rigid mounting between the frame and the undercarriages. Because of its rigidity, this type of mounting between the frame and the undercarriages can transfer machine-induced loads and vibrations to an operator, making long periods of machine usage uncomfortable for the operator.
To help absorb at least some of these machine induced loads and vibrations, some compact construction machines may include a suspension system in the form of multiple torsion axle assemblies. Each torsion axle assembly may include a torsion arm, a torsion shaft, and an axle. The torsion shaft and the axle may extend in different directions from opposing ends of the torsion arm. The torsion shaft of each torsion axle assembly may be rigidly attached to the frame while the axle is attached to a surface of the undercarriage of the machine.
During operation of the machine, the torsion axle assemblies may flex. In particular, the individual torsion arms may rotate against a cushion of rubber cords located within the torsion shaft. This cushioned rotation absorbs some of the loads and vibrations induced on the undercarriages of the machine during operation, thereby preventing such loads and vibrations from being transferred to the machine frame and the machine operator. However, the operation of the torsion axle assemblies can limit an operator's ability to feel the movement of the machine and the contours of the work surface. This may be an issue during certain working operations in which fine control of the machine may be desired.